Automatic brake releasing means



' May 12, 1970 Fiied Feb. 8, 1968 w. T; PRITCHARD AUTOMATIC BRAKERELEASING MEANS 2 Sheets- Sheet 1 INVENTOR WILLIAM TI Pzrrcamzo O MMQATTORNEYS Maw All? SUPPLY May 12; 1970 w. T. PRITCHARD ,511,

AUTOMATIC BRAKE RELEASING MEANS Filed Feb. 8, 19 68 2 Sheets-Sheet 2llllllllllllllllllllllllfi 'lllilm I I L P 23 if tg a 'lgA M- I I 7 545e 3 I'NVENTOR WlLLlAM T Pczrro-mrzo ATTORNEYS United States Patent O3,511,347 AUTOMATIC BRAKE RELEASING MEANS William T. Pritchard, Beckley,W. Va., assignor of onefourth each to John C. Ashworth and Robert J.Ashworth, both of Beckley, W. Va.

Filed Feb. 8, 1968, Ser. No. 703,940 Int. Cl. F16d 65/32; F16h 21/44 US.Cl. 188-216 8 Claims ABSTRACT OF THE DISCLOSURE BACKGROUND OF THEINVENTION This invention is related to the field of braking apparatusand is specifically related to the field of railway train brakingsystems and is specifically directed to means for automaticallydeactivating the mechanical brakes of a railroad car upon connection ofthe car to the compressed air line of a train.

Railroad cars are provided with mechanical brakes which are actuated bymeans of a brake-setting handwheel assembly usually located adjacent oneend of the car. When a railroad car is parked on a siding, it isnecessary to set the mechanical brakes in order to insure that the carwill remain in its parked position. Therefore, when it is desired tomove the car, it is necessary that the mechanical brakes be released,This releasing operation requires a great deal of physical exertion onthe part of the brakeman and it is also quite time consuming. Moreover,the problem is greatly aggravated when there are a large number of carswhich must be released and it sometimes occurs that all of themechanical brakes will not be released so as to result in sliding of thecar wheels along the track when the cars are connected to a locomotive.Also, it sometimes occurs that the brakes are not completely releasedand, while the wheels do not drag, there is a resultant wear and tearupon the braking system and the rails. For these reasons, it is highlydesirable that means be provided for automatically releasing themechanical brakes of a railroad car upon connecting of the car to othercars or locomotives prior to movement of the car from its parkedposition.

SUMMARY OF THE INVENTION Therefore, it is the primary object of thisinvention to provide means for automatically releasing the mechanicalhand-set brakes of a railroad car upon connection of the car to the maincompressed air supply line of another car or of a locomotive.

The primary object of this invention is obtained by the provision of apneumatic cylinder mounted on the car adjacent the conventionalmechanical brake-setting handwheel assembly of the car. This pneumaticcylinder is provided with a rack attached to the end of the piston rodof the cylinder and the cylinder is connected to a line connected to themain air supply coupling of the car. When the main air line supplycoupling is connected to the compressed air line of another car, thecylinder is actuated to extend the piston so that the rack engages agear mounted on the handwheel supporting shaft of the manualbrake-setting means. Engagement of the rack with the gear serves torotate the manual setting means in a direction to release the mecahnicalbrakes so that the car can then be moved without brake or wheeldragging. A

3,511,347 Patented May 12, 1970 shutoff valve is provided in the airline connecting the cylinder with the main air supply coupling in orderto prevent activation of the cylinder is such as desired. Moreover, themeans supporting the pneumatic cylinder is adjustable so that theposition of the cylinder can be adjusted.

DESCRIPTION OF THE DRAWINGS FIG.1 is a perspective view of the preferredembodiment of the subject invention mounted on the end of a railway car;

FIG. 2 is a partial sectional view taken along lines 2--2 of FIG. 1;

FIG. 3 is a partial sectional view substantially identical with FIG. 2but illustrating the parts in a different operative relationship withrespect to each other; and

FIG. 4 is a sectional view taken along lines 44 of FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENT The preferred embodiment of thisinvention is perspectively illustrated in FIG. 1 as installed on the endof a railway car 20. The car is provided with a conventional linkagesystem consisting of a vertical link 22 connected to the upper arm of aright angle pivot lever 24 pivotally attached to the frame of the car.The upper end of link 22 is connected by a chain 26 which extends into aconventional brake actuator housing 28 which contains rotary means forraising and lowering the chain. A horizontal link 30 extends between thelower arm of pivot lever 24 and the mechanical brakes of the car (notshown) so that lifting movement of chain 26 and rod 22 serves to movethe horizontal link 30 so as to set or engage the mechanical brakes ofthe car. Chain 26 is raised or lowered by rotation of a brake-settingwheel 32 which is fixed to a shaft 34 extending from housing 28. Theaforediscussed construction is conventional and while the prior artconstructions employ various minor variations, all of the knownmechanical brake-setting devices employ a shaft mounted rotatable wheelsuch as wheel 32 for setting the brakes.

Therefore, the prior known devices require a manual operation of thesetting wheel 32 in order to effect setting of the brakes and similarlyrequire a manual operation for disengaging the brakes when it is desiredto move the. car. This invention avoids the necessity of the latteroperation.

Turning now to FIG. 1, it will be seen that this invention includes asupport means or bracket 36 fixedly attached to the end wall of therailroad car 20, First and second U-shaped bolts 38 and 40 have theirouter ends extending through apertures in support means 36 and areretained in place by nuts 42 and 44 respectively. The apertures throughwhich bolts 38 and 40 extend can be in the form of slots to permitadjustment of the bolts. The U-shaped bolts 38 and 40 clamp a pneumaticcylinder 46 in a desired adjustably fixed relationship with respect tothe support means 36 when nuts 42 and 44 are tightened.

A piston 48 is contained within cylinder 46 for reciprocation in aconventional manner and a piston rod 50 extends outwardly from one endof the cylinder through a slide bearing 52. A small bleed hole 53 isprovided adjacent slide bearing 53 for the purpose of controlling thespeed with which the piston 48 moves. The other end of pneumaticcylinder 46 is provided with a port 54 to allow the entry of compressedair to the interior of the cylinder. An air line 56 is connected to port54 as shown in FIG. 2 and is provided with a gate valve 58. The side ofgate valve 58 opposite to the connection to pneumatic cylinder 46extends downwardly for connection to the main air supply coupling (notshown) of the car 20. When the car is connected to another car, the mainair supply coupling is connected to a like coupling on the other car sothat compressed air will consequently be provided to line 56 so as toactuate cylinder 46 and cause piston 48 to move so as to extend pistonrod 50 from the cylinder 46. Obviously, when valve 58 is closed,compressed air cannot reach the pneumatic cylinder 46 to actuate thecylinder.

The outer end of rod 50 has a rack member 60 pivotally attached theretoby means of pivot means 62. The lower end of rack 60 is provided with aplurality of teeth 64 which engage a gear wheel 66. While gravitationalurging has proven adequate for maintaining teeth 64 in engagement withgear 66, a supplemental biasing spring can be provided to engage the topof rack 60 for this purpose if desired. Gear wheel 66 is mounted in asupplemental gear housing 67 fixed to shaft 34 so that rotation of thegear wheel rotates the shaft to consequently move chain 26, link 22 etc.so as to affect the brake setting. Housing 67 is provided with slots oneither side enabling entry and movement of rack 60 in an obvious manneras shown in FIG. 3.

A coil spring 70 is provided on the interior of cylinder 46 inencircling arrangement with piston rod 50 as illustrated in FIG. 4. Thecoil spring 70 serves to bias the piston 48 to the right in an obviousmanner.

When the manual brakes of a railway car are to be set, handwheel 32 isrotated to its extreme clockwise position and the parts assume theposition illustrated in FIG. 2 with the piston and piston rod assemblybeing in its extreme rightward position. It should be noted that thepiston assembly will return to its rightmost position at the time theair coupling of the car is disconnected from the source of compressedair with spring 70 providing the motive force for returning the pistonto the position illustrated in FIG. 4. The teeth on rack 60 are shapedso that the rack teeth will ride over gear wheel 66 during rack movementfrom left to right as will be obvious from inspection of the rack teethand gear teeth in FIG. 3. However, it sometimes occurs that themechanical linkage for setting the brakes contains an excessive amountof play and it may be necessary to provide additional rotation ofhandwheel 32 and gear 66 to complete setting of the mechanical brakeswhen the parts are in the position illustrated in FIG. 3. Obviously,engagement of teeth 64 on rack 60 would preclude the additional rotativemovement necessary for the handwheel 32 and gear 66. Therefore, in suchsituations, rack 60 is pivoted counterclockwise upwardly so that teeth64 are disengaged from gear 66 to enable the completion of the settingof the manual brakes without interference from gear teeth 64. Apivotable stop or latch can be provided on the end of the car forholding the rack in this upward position if such is desired. Such alatch could be in the form of a pivot plate pivotally connected to theend of the car beneath rack 60' so as to be pivoted upwardly beneath therack to lift same. An abutment extending downwardly from the bottom ofthe rack so as to engage the pivot latch upon actuation of cylinder 46would serve to pivot the latch out of supporting relationship withrespect to the rack so that the rack would move downwardly to engagegear 66 upon actuation of cylinder 46.

Therefore, when the railway car is in a parked condition, with themechanical manually actuated brakes set, the parts are in the positionillustrated in FIG. 2. However, when it is desired to move the car, itis coupled to an adjacent car or locomotive for movement. Coupling ofthe car to an adjacent car requires connection of the air hose couplingto the air hose coupling of the adjacent car and this connectionsupplies compressed air through lines 56 to actuate cylinder 46.Consequently, the cylinder is actuated to move the piston rod and pistonassembly to its leftward extended position illustrated in FIG. 3. Thismovement causes gear teeth 64 to rotate gear 66 to release the manuallyset mechanical brakes in an obvious manner. The bleed hole 53 controlsthe rate of movement of the piston and piston rod assembly in an obviousmanner.

When the car is subsequently parked, the air coupling will bedisconnected so that spring 70 will return the piston to the positionillustrated in FIGS. 2 and 4. The shape of the teeth 64 is such toenable this movement as was discussed previously. The brakes can then bemechanically set by rotation of handwheel 32. However, in some instancesit might be desirable to set the mechanical brakes prior todisconnection of the air coupling. In which cases, rack 60 could bepivoted upwardly so that teeth 64 are disengaged with gear wheel 66 soas to allow rotation of handwheel 32 to effect setting of the manuallyset mechanical brakes without interference from teeth 64.

What is claimed is:

1. In a railroad car of the type having manually set mechanical brakeswhich are set by rotation of a shaftmounted brake-setting wheel, theinvention comprising an improved releasing means automatically actuatedby connection of the compressed air line of the railroad car to a sourceof compressed air, said brake releasing means including an air cylindercontaining a piston and extendable piston rod, rack means connected tothe end of said piston rod, gear means on said shaft engaged with saidrack, a compressed air supply line connected between said cylinder andthe main air supply coupling of the car and supporting meanssupportingly attached said cylinder to said railroad car in a positionadjacent said brakesetting wheel so that connection of the compressedair line to said source of compressed air causes said cylinder to beactuated to extend said cylinder to rotate said gear wheel mounted onsaid shaft on which said brake-setting wheel is mounted to consequentlyrelease the mechanical brakes.

2. The invention of claim 1 wherein said rack means is attached to theend of said piston rod by means of a pivot connection for permittingsaid rack to be pivoted out of engagement with said gear wheel.

3. The invention of claim 2 additionally including valve means in saidcompressed air supply line actuable when closed to prevent automaticoperation of said brake releasing means.

4. The invention of claim 3 additionally including spring means withinsaid cylinder for biassing said piston and piston rod in a directionopposite to the direction of movement of said piston and piston rod whensaid piston is actuated by compressed air.

5. The invention of claim 4 wherein said supporting means includes meansenabling the adjustment of the position of said cylinder with respect tosaid gear wheel.

6. The invention of claim 2 wherein said gear wheel is mounted on ahorizontal shaft and said rack is pulled downward by the force ofgravity into engagement with said gear but is pivotable upwardly againstthe force of gravity out of engagement with said gear.

7. The invention of claim 6 additionally including valve means in saidcompressed air supply line actuable when closed to prevent automaticoperation of said brake releasing means.

8. The invention of claim 7 additionally including spring means withinsaid cylinder for biassing said piston and piston rod in a directionopposite to the direction of movement of said piston and piston rod whensaid piston is actuated by compressed air.

References Cited UNITED STATES PATENTS 1,459,650 6/1923 Burnett 74109 X1,819,952 8/1931 Fink l88216 DUANE A. REGER, Primary Examiner US. Cl.X.R.

